That's the tradeoff, of course. If a company liquidates, it pays its debts first, then its preferred stockholders, then its common stockholders. But each step down the line gives a greater upside in exchange for less certainty in getting paid at all. Bondholders get paid at higher priority, but have the exact amount they get paid defined by a specific mathematical formula. So they won't get any additional benefit from the company becoming super valuable. Or they can get in the back of the line to see what unlimited upside they have from the company's value going up a lot.

Also, Anthropic's bonds aren't exactly low interest. They're right there at the edge between junk bond and investment grade.